NOTE: Not to dispute the value of these siesmic records, when the authors state, "We understand from news reports that the first impact (0846 EDT) resulted in the second collapse (1028 EDT), and the second impact (0903 EDT) resulted in the first collapse (0959 EDT)", they are imposing a causal connection that might not obtain. The temporal relations hold, since WTC1, hit first, fell second, and WTC2, hit second, fell first, so it would be more accurate to assert, "The first impact (0846 EDT) was followed by the second collapse (1028 EDT), and the second impact (0903 EDT) by the first collapse (0959 EDT)", but not that either collapse was a "result" of the impacts that preceded them. Indeed, even to assume that these effects were brought about by "impacts" or by "collapses" is to go beyond the evidence that the seismic records themselves provide by drawing inferences as to their causation.